Molecular Mimicry Study Between Peptides of SARS-CoV-2 and Neutrophil Extracellular Traps Related Proteins

Background: Neutrophil extracellular traps (NETs) are observed in both COVID-19 pathology and autoimmune disorders, and molecular mimicry is a mechanism that can lead to autoimmune response. Methods. Accordingly, homologous sequences between SARS-CoV-2 proteins and 5 proteins (plasminogen receptor KT: PLRKT, myeloperoxidase: MPO, proteinase 3: PR-3, neutrophil elastase: NE, matrix metalloproteinase 9: MMP-9) that are present in NETs, are searched. Human and SARS-CoV-2 sequence pairs are identified. Those among the identified sequence pairs, which are strong-binding peptides or epitopes of the same HLA alleles, are predicted. Results. PLRKT and SARS-CoV-2 similar peptides with high affinities to HLA-A*24:02, HLA-B*08:01, and HLA-B*15:01; MPO and SARS-CoV-2 similar peptides with strong affinities to HLA-A*01:01, HLA-A*26:01 and HLA-B*15:01; and MMP-9 and SARS-CoV-2 similar peptides with elevated affinity to HLA-B*39:01, are detected. Conclusions. This is a proof of the concept study, which revealed potential involvement of molecular mimicry in NETs-pathology within susceptible individuals, in case of being infected with SARS-CoV-2.